I have had fixed wireless NBN service for 3+ years and it's generally been OK up until the last few weeks. There was a flurry of NBN service warnings from Optus, that apparently have now finished, but since then, almost every night from about 7pm the speed drops to almost nothing, making it totally useless to do anything at all, not to mention stream video. Ookla speedtests during the day come in at about 20-40Mbps during the day (which is usable but not great) but drops to 1-2Mbps at night which simply doesn't do anything. This was a very sudden shift, not gradual and I initially figured it was teething issues after the service, but it does not appear to be going away. Has anyone else experienced this sort of issue and had any joy in getting it fixed?